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<span id="ATOMIC_005fDEFINE"></span><div class="header">
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<span id="ATOMIC_005fDEFINE-_002d_002d_002d-Setting-a-variable-atomically"></span><h3 class="section">8.31 <code>ATOMIC_DEFINE</code> &mdash; Setting a variable atomically</h3>
<span id="index-ATOMIC_005fDEFINE-1"></span>
<span id="index-Atomic-subroutine_002c-define"></span>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>ATOMIC_DEFINE(ATOM, VALUE)</code> defines the variable <var>ATOM</var> with the value
<var>VALUE</var> atomically. When <var>STAT</var> is present and the invocation was
successful, it is assigned the value 0. If it is present and the invocation
has failed, it is assigned a positive value; in particular, for a coindexed
<var>ATOM</var>, if the remote image has stopped, it is assigned the value of
<code>ISO_FORTRAN_ENV</code>&rsquo;s <code>STAT_STOPPED_IMAGE</code> and if the remote image has
failed, the value <code>STAT_FAILED_IMAGE</code>.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>Fortran 2008 and later; with <var>STAT</var>, TS 18508 or later
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Atomic subroutine
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><p><code>CALL ATOMIC_DEFINE (ATOM, VALUE [, STAT])</code>
</p>
</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>ATOM</var></td><td width="70%">Scalar coarray or coindexed variable of either integer
type with <code>ATOMIC_INT_KIND</code> kind or logical type with
<code>ATOMIC_LOGICAL_KIND</code> kind.</td></tr>
<tr><td width="15%"><var>VALUE</var></td><td width="70%">Scalar of the same type as <var>ATOM</var>. If the kind
is different, the value is converted to the kind of <var>ATOM</var>.</td></tr>
<tr><td width="15%"><var>STAT</var></td><td width="70%">(optional) Scalar default-kind integer variable.</td></tr>
</table>

</dd>
<dt><em>Example</em>:</dt>
<dd><div class="example">
<pre class="example">program atomic
  use iso_fortran_env
  integer(atomic_int_kind) :: atom[*]
  call atomic_define (atom[1], this_image())
end program atomic
</pre></div>

</dd>
<dt><em>See also</em>:</dt>
<dd><p><a href="ATOMIC_005fREF.html">ATOMIC_REF</a>, <br>
<a href="ATOMIC_005fCAS.html">ATOMIC_CAS</a>, <br>
<a href="ISO_005fFORTRAN_005fENV.html">ISO_FORTRAN_ENV</a>, <br>
<a href="ATOMIC_005fADD.html">ATOMIC_ADD</a>, <br>
<a href="ATOMIC_005fAND.html">ATOMIC_AND</a>, <br>
<a href="ATOMIC_005fOR.html">ATOMIC_OR</a>, <br>
<a href="ATOMIC_005fXOR.html">ATOMIC_XOR</a>
</p></dd>
</dl>






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